cc -pthread  -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations fcntl/struct-flock.c -o fcntl/struct-flock -D_POSIX_C_SOURCE=202405L -lm -lpthread -lrt -lintl -liconv
fcntl/struct-flock.c:2:14: error: storage size of ‘foo’ isn’t known
    2 | struct flock foo;
      |              ^~~